Shaped like an eyelid in a halo of azure water, the tiny Indian Ocean island of Dhuvaafaru in the Maldives is a fresh-minted community that has been transplanted to the Raa atoll. Clinics, schools and roads have all been built from scratch. Its homes, all newly peopled, are the legacy of tragedy on a vast scale: 2004's Boxing Day tsunami.

This year – at the culmination of the single biggest construction project in Red Cross/Red Crescent history – 4,000 people from the nearby low-lying island of Kandholhudhoo, a place made uninhabitable by the waves that destroyed houses and snapped trees like matchsticks, were finally moved to Dhuvaafaru on the opposite side of the archipelago to begin new lives.

Among them was Hussain Alifulhu, 48, one of the last to escape the island when the tsunami swamped his home. He was among those who helped build the new community, an electrician by trade who spent the last four years living with his family in temporary shelters, fishing for sea cucumbers to make a living. On his new island home, he is working as an electrician once again.

The story of Dhuvaafaru is a reflection of the scale of a recovery operation that continues to this day, although in its last stages – the response to a disaster that claimed 228,000 lives in 13 countries from the coast of Africa to Indonesia in the space of a few hours, among them tens of thousands of children. It displaced 2 million more. The tsunami destroyed towns, villages and livelihoods. Half a million houses were damaged or destroyed. Fields and wells were poisoned with saline water. It obliterated lives and upset the entire composition of societies.

But the little island of Dhuvaafaru is the symbol of a relief effort that, by and large, has been regarded as an overwhelming success, rewriting the rules of how best to respond to a major disaster: by empowering its victims to reconstruct their lives rather than imposing aid upon them.

The source of the catastrophe five years ago was a massive undersea earthquake off the island of Sumatra. With a magnitude of 9.3 it was the second-largest seismic event recorded, and the largest tsunami. At their highest, the waves reached almost 30 metres.

While 9,000 foreign tourists died in seaside resorts around the Indian Ocean, the biggest victims by far were the host communities, in particular in Indonesia's Aceh and Northern Sumatra, where 167,000 people died.

For the International Federation of Red Cross societies alone, the figures from the last five years have been staggering, reflecting the scale of its biggest civil recovery operation.

Since 2004 it has provided 4,807,000 people with assistance; 51,395 new houses have been built; 289 hospitals and clinics built or rehabilitated. Pledged international aid from all sources for the recovery has topped $13.5bn, almost half of it given by private individuals and organisations.

That sum stands as a powerful measure of the scale of a disaster that unfolded half a decade ago – whose physical reminders have all but been erased in the reconstruction effort but whose reality has not been wiped from a generation's collective memory.

For the victims a different reality persists, less visible but present all the same, to be found in recollection of the missing and the dead, and the still lingering, faint hope that a lost relative – or at least their body – might yet return.

In Thailand, even today, family members still call into the TTVI centre, the office tasked with finding and identifying the dead, in the hope that officials might have linked one of 300 unclaimed and unidentified bodies buried in the grave site in Phang Nga province, marked by a giant concrete wave, with a name of the missing.

But the monument to the tsunami's nameless victims is the exception, not the rule, in a country where few physical reminders of the disaster remain. In Khao Lak beach, for instance, where 3,000 people died, all that is left are the occasional "tsunami hazard" signs and the colour-coded evacuation routes set up in the aftermath of the disaster. Even the Marriott resort and spa, where 300 died, has reopened for business.

In Banda Aceh, what little wreckage remains has been appropriated as something for curious sightseers. The 2,600-tonne PLTD Apung cargo vessel, which was swept inland in 2004, sat in the middle of a vista of flattened buildings and the tented accommodation of the survivors. These days it is a tourist landmark surrounded by the roofs of rebuilt houses.

Others things have changed in the last five years. On Boxing Day 2004 – as the US National Oceanic and Atmospheric Administration and others have conceded – the lack of an effective tsunami warning system contributed to the huge death toll. Then there were six experimental tsunami buoys in existence. Today an operating network of 39 exists, comprehensively tested for the first time in October.

But if many of the affected areas on the Indian Ocean coast have physically recovered, guided by the motto "build back better", what has been more difficult to assess has been the complex social, political and personal consequences of the catastrophe.

In villages in Aceh, where the tsunami killed a disproportionate number of women, unable to swim and encumbered by sarongs that made it hard for them to flee, a generation of young men exists who struggle both to find work and women to marry.

The impact of what happened that day has stretched far beyond the obvious. The tsunami acted as the midwife to a surprising peace settlement in Aceh, and as a dangerous accelerant to conflict in Sri Lanka.

Five years on, it is the stories of individuals that still remain most striking. And the loss that clings to their memories.

Nok, a resident of Phang Nga province, was 11 when the tsunami struck and still recalls the moment she saw the "big wave" rising above the others as she stood on the beach with her younger brother, watching the water, waiting for their parents' fishing boat to return. "I'd never heard of tsunami, I didn't know what it was." Her aunt did. "She was screaming at me 'run, run, run'. I didn't get far, only just outside when the wave hit me, it pushed me against the wall, very hard, and it pushed me along."

Nok's brother, still on the beach, was caught up in the wave too. It dragged him inland before sucking him back out to sea. He was rescued by a fisherman who thought his cries for help had come from a ghost. "It was nine o'clock in the night-time that I could find my brother alive. I thought he was dead."

Nok's mother did not survive. Her body was never found. The wave took Nok's aunt, too, and her grandparents. Her father survived the wave, but could no longer look after his children. Now 16, Nok lives with her brother in a community-run home set up for children orphaned by the tsunami. "Every 26 December is an important day. It is a very sad day. I can never forget what happened. The wave took my family."

But for many life has moved on – in large part assisted by international aid agencies, including Oxfam. Aisyah Harun, 49, lost her husband, three children, and two grandchildren. She was reliant on Oxfam, the first aid agency to reach her village, for a micro-loan to buy baking tools and ingredients. "I was very happy to have them back after I lost everything," she says. "The reason I wanted to start my business again as soon as possible wasn't only because I needed to, but I want to kill the trauma and not remember the bad things. So I wanted to work."

But while most tsunami-affected territories have re-emerged physically – if not psychologically – better, not everywhere has recovered at the same pace, including India's Tamil Nadu.

"What is bad is that in the villages on the seashore there has been little clean-up. We can still find boats left five years on which had been washed up and have not been cleaned up. It's more than an eyesore," said Bhatkher Solomon, chief executive officer of the NGO Development Promotion Group.

Sri Lanka, in terms of its population, was the worst hit during the tsunami, and it has also suffered worst in the aftermath, seeing the least coherent recovery – one that allowed a return to war. The Tamil Tigers' monopoly on control of large areas of the country's north and east allowed it to dictate terms to the aid agencies pouring in cash. Money was diverted to buying arms and consolidating military strength. Eventually the two-year long ceasefire collapsed into fighting that only ended this year with the Tigers' final defeat.

"A lot of international agencies with no experience in the country were trying to replicate responses to an African disaster model. This led to waste and things done inappropriately. We had fishing boats given to people who were not fishermen. Too many boats led to overfishing. Giving nets that were not appropriate for our waters. Not looking at agriculture. But you learn," said PB Gowthaman, Sri Lanka country director for Oxfam Australia.

Having dealt with the tsunami, Sri Lanka now faces having to resettle "a million people" displaced by the end of three decades of war between the Tigers and the Sri Lankan army. "It's twice the size of the tsunami," said Gowthaman.